We have done outside soccer fields with a paint machine. We use their paint and machine. Striping the field we do takes about 2 hours to prep the machine, paint, and then clean our tools. I would figure on a normal hourly rate for two employees. That is how we do it. We use mowing as our example. Whatever your average hourly rate is for four man hours is what I would go with, just remember if you have to measure and lay out the field it takes extra time and possibly manpower